<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="vue.js"></script>
</head>
<body>
    <div id="app">
        <h3>银行账户余额变更通知</h3>
        <p>账号：3001237890122</p>
        <p>余额为：{{count}}</p>
        支取人民币：<input type="text" v-model="money"/>&nbsp;&nbsp;
        <button type="button" @click="changeMoney()">支取{{money}}元</button>
        <p>支取后余额为：{{count}}元</p>
        <h3>以下是支出明细帐</h3>
        {{detail}}
        <hr>
    </div>
</body>
<script type="text/javascript">
    const appCom={
        data(){
            return{
                count: 10000,//余额
                money:500,//取款金额
                record:[]//取款金额记录
            }
        },
        watch:{
            count(newValue,oldValue){
                alert('账户余额由：'+oldValue+'变为'+newValue+'元！');
            }
        },
        methods:{
            changeMoney(){
                if(this.money<=0){
                    alert('请输入正确的取款金额！');
                    return;
                }
                if(this.money>this.count){
                    alert('余额不足，请重新输入取款金额！');
                    return;
                }
                this.count=this.count-this.money;
                this.record.push(this.money);
            }
        },
        computed:{
            detail(){
                let str="";
                for(let i=0;i<this.record.length;i++){
                    str=str+'第'+(i+1)+'次取款：'+this.record[i]+'元；';
                }
                return str;
            }
        }
    };
    Constapp=Vue.createApp(appCom).mount("#app");
</script>
</html>